Universal motion of mirror-symmetric microparticles in confined Stokes flow
Universal motion of mirror-symmetric microparticles in confined Stokes flow
复制标题
DOI：
10.1073/pnas.2005068117
复制
发表时间：
2020-09-08
影响因子：
11.1
通讯作者：
Eral, Huseyin Burak
中科院分区：
文献类型：
--
作者：
Georgiev, Rumen N.;Toscano, Sara O.;Eral, Huseyin Burak
全面了解微流体装置中的颗粒运动对于解锁基于形状的微颗粒分离和分选（如微塑料，细胞和晶体多晶）的其他技术至关重要。这些粒子与封闭表面发生流体动力学作用，从而改变了它们的轨迹。这些流体动力学的相互作用与形状有关，可以调整以引导粒子沿着特定的路径运动。我们利用止流光刻技术在浅微流控通道中制造出各种形状的强约束颗粒。无论它们的确切形状如何，具有单一镜面的粒子具有相同的运动模式：平面内旋转和沿钟形路径的横流平移。每种模式都有一个特征时间，由粒子几何形状决定。此外，每个粒子的轨迹可以通过其各自的特征时间缩放到两条主曲线上。我们提出将这些时间尺度与粒子形状联系起来的极简主义关系。这些主曲线合在一起，就产生了具有单一镜面的粒子的通用轨迹。
Comprehensive understanding of particle motion in microfluidic devices is essential to unlock additional technologies for shape-based separation and sorting of microparticles like microplastics, cells, and crystal polymorphs. Such particles interact hydrodynamically with confining surfaces, thus altering their trajectories. These hydrodynamic interactions are shape dependent and can be tuned to guide a particle along a specific path. We produce strongly confined particles with various shapes in a shallow microfluidic channel via stop flow lithography. Regardless of their exact shape, particles with a single mirror plane have identical modes of motion: in-plane rotation and cross-stream translation along a bell-shaped path. Each mode has a characteristic time, determined by particle geometry. Furthermore, each particle trajectory can be scaled by its respective characteristic times onto two master curves. We propose minimalistic relations linking these timescales to particle shape. Together these master curves yield a trajectory universal to particles with a single mirror plane.